Compositions containing 2-acetyl-1-pyrroline

ABSTRACT

A powder-form composition of 2-acetyl-1-pyrroline incorporated with a support of maltodextrin and/or cyclodextrin. The composition is prepared by hydrolyzing a 2-(1-alkoxyethenyl)-1-pyrroline with an acid to obtain a reaction medium, adding an equimolar amount of a base to the reaction medium to obtain a neutralized reaction medium containing 2-acetyl-1-pyrroline, combining maltodextrin and/or cyclodextrin with the neutralized reaction medium to obtain a support solution and freeze-drying the support solution to obtain the composition.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional application of Application Ser. No.08/158,934, filed Nov. 29, 1993 now U.S. Pat. No. 5,401,521 and which,in turn, is a divisional application of application Ser. No. 07/979,293,filed Nov. 20, 1992, now U.S. Pat. No. 5,280,127.

BACKGROUND OF THE INVENTION

This invention relates to compositions containing 2-acetyl-1-pyrroline.

U.S. Pat. No. 4,522,838 (Buttery, et al.) describes a process for theproduction of 2-acetyl-1-pyrroline. This process comprises catalyticallyreducing 2-acetyl pyrrole for 15 hours under a hydrogen pressure ofapproximately 0.7 bar, to obtain (1-hydroxyethyl)-2-pyrrolidine as anintermediate product, and oxidizing the intermediate product obtainedwith silver carbonate under reflux in benzene, again over a period of 15hours. The 2-acetyl-1-pyrroline is then isolated by gas phasechromatography using a capillary column 2 metres in length and 6.4 mm indiameter. The 2-acetyl-1-pyrroline thus obtained has a purity ofapproximately 95%, but can only be produced in small quantities at atime, due mainly to the purification of the compound by gas phasechromatography. In addition, the 2-acetyl-1-pyrroline is unstable andhas to be stored at a temperature preferably below 0° C., which makes itdifficult to use, particularly on an industrial scale.

Another process for the production of 2-acetyl-1-pyrroline frompyrrolidine is known from European Patent Application Publication No.436 481, but does not solve the problem in question.

SUMMARY OF THE INVENTION

The present invention includes powder-form compositions containing2-acetyl-1-pyrroline and in particular, 2-acetyl-1-pyrrolineincorporated with a support of maltodextrin, cyclodextrin, orcombinations thereof. The compositions are prepared by hydrolyzing a2-(1-alkoxyethenyl)-1-pyrroline compound with an acid to obtain areaction medium, neutralizing the reaction medium with an equimolaramount of a base to obtain a neutralized reaction medium containing2-acetyl-1-pyrroline, combining a support of cyclodextrin, maltodextrin,or combinations thereof with the reaction medium to obtain a supportsolution and freeze-drying the support solution to obtain thecomposition. The composition provides the 2-acetyl-1-pyrroline in astable form which can be stored for a certain time at ambienttemperature.

DETAILED DESCRIPTION OF THE INVENTION

In preparing compositions of the present invention, a2-(1-alkoxyethenyl)-1-pyrroline compound, which may be2-(1-ethoxyethenyl-1-pyrroline, is hydrolyzed with an acid, preferably amineral acid, such as hydrochloric acid, and then, the reaction mediumis neutralized with an equimolar amount of a base, preferably a strongbase, such as sodium hydroxide, which may be added by dropwise additionwith stirring. The 2-(1-alkoxyethenyl)-1-pyrroline compound to behydrolyzed preferably is in a concentration of from 2% to 30%, and thereaction medium obtained by hydrolysis may be diluted with water beforeaddition of the base.

When the support employed is cyclodextrin, it is combined in solution orin a dry form with the neutralized solution so that a solutioncontaining up to 20% by weight 2-acetyl-1-pyrroline, based on the weightof the cyclodextrin, is obtained. β-cyclodextrin preferably is employed.

When the support is maltodextrin, it is combined in solution or in a dryform with the neutralized solution so that a solution containing up to10% by weight 2-acetyl-1-pyrroline, based on the weight of themaltodextrin, is obtained. Additionally, gum arabic also may beincorporated into the neutralized solution with the maltodextrin.

The foregoing steps preferably are carried out at a temperature in therange of from -10° C. to 25° C., and it is important to bear in mindthat the higher the temperature, the greater the risk of decompositionof the 2-acetyl-1-pyrroline and the greater the need to work quickly toreduce that risk.

After support addition, the solution is freeze-dried, and when thesupport is added in dry form, rather than in solution, such may enablereduction of the amount of water to be removed, which therebyfacilitates the freeze-drying.

Operating in accordance with the present invention, therefore, enablesobtaining a composition of 2-acetyl-1-pyrroline incorporated with asupport in a form of a powder which may contain up to 20% by weight of2-acetyl-1-pyrroline based on the weight of the powder, and inparticular, up to 20% when cyclodextrin is the support and up to 10%when maltodextrin is the support.

Accordingly, the present invention also relates to the use of2-(1-alkoxyethenyl)-1-pyrroline compounds which correspond to thefollowing general formula: ##STR1## with R=alkyl.

These compounds may be obtained by a process in which the correspondingalkyl vinylethyl compound is reacted with tert, butyl lithium in organicsolution, for example in pentane, tetrahydrofuran or ether, or in amixture of these solvents, N-trimethylsilyl-2-pyrrolidinone is thenadded and the mixture is left to react, preferably below 0° C., thesolution obtained is hydrolyzed, the organic phase is recovered, driedand purified to obtain the required 2-(1-alkoxyethenyl)-1-pyrroline. Thehydrolysis is preferably carried out by addition of water or a solutionof ammonium chloride. After hydrolysis, a salt, such as sodium chloride,may be added to saturate the solution so that the yield of the processcan be improved.

The final purification step may be carried cut by any method, such asdistillation and/or column chromatography.

Accordingly, compounds of the 2-(1-alkoxyethenyl)-1-pyrroline type canbe obtained by this process and may be used for the production of2-acetyl-1-pyrroline. It has also been found that one of the compoundsof this type, namely 2-(1-ethoxyethenyl)-1-pyrroline, has certainorganoleptic qualities which enable it to be used on its own or incombination as a flavouring agent. These organoleptic characteristicsmay be described thus as grilled, fruity, hazel nuts and reminiscent ofthose of pyrazine.

EXAMPLES

The invention is illustrated in more detail in the following Examples inwhich parts and percentages are by weight wherein Examples 1-3illustrate preparation and properties of2-(1-ethoxyethenyl)-1-pyrroline, and Examples 4-6 illustrate preparationof 2-acetyl-1-pyrroline and preparation of compositions including thatcompound incorporated with a support and properties thereof.

Example 1

A solution containing 54.1 g ethylvinyl ether in 300 ml tetrahydrofuran(THF) is prepared.

This solution is cooled to -40° C. and a 1.4N solution of 429 mltert-butyl lithium in pentane is added dropwise to the solution. Themixture is then stirred continuously for 12 hours at -40° C., afterwhich a solution of 47.1 g of N-trimethylsilyl-2-pyrrolidinone in 300 mlTHF is added. The mixture thus obtained is stirred continuously for 7hours at -40° C., after which 32.1 g ammonium chloride dissolved in 300ml water are added. The mixture is then left to return to approximately0° C. and is then saturated by addition of 60 g sodium chloride. Thesolution is then left standing so that the aqueous phase and organicphase can separate. The organic phase is recovered and the aqueous phaseis extracted three times with 50 ml ether.

The various organic fractions obtained are mixed, washed three timeswith 50 ml water saturated with NaCl and then dried over sodium sulfateand the solvents are evaporated under reduced pressure. 37.8 g crudeextract are obtained in the form of a yellow liquid. A chromatographycolumn 4 cm in diameter and 80 cm in height containing 500 g of a silicagel is prepared. A solution containing 20 parts dichloromethane to 1part ethyl acetate is used as eluent. The crude extract diluted with theeluent is introduced into the column and is then eluted at a rate of 2ml per minute. A 99.9% pure compound in the form of a colourless liquidis obtained in a yield of 17.1 g.

Example 2

1. Mass spectrum

The mass spectrum of the compound obtained in accordance with Example 1gives the following results:

    ______________________________________           Relative intensity    m/z    (100 = base peak)                            Identification    ______________________________________    139     8                M!.sup.+ Molecular peak    124    21                M--CH.sub.3 !.sup.+    110     5                M--C.sub.2 H.sub.5 !+    95     100               M--CH.sub.3 CHO!.sup.+    94     66                M--OC.sub.2 H.sub.5 !+    83      6               --    82     10               --    67     18               --    41     30               --    ______________________________________

2. Elemental analysis

Elemental analysis of the compound obtained in accordance with Example 1by combustion gave the following results:

    ______________________________________                      %    ______________________________________    C             Observed  68.70                  Calculated                            69.03    H             Observed   9.26                  Calculated                             9.41    N             Observed   9.74                  Calculated                            10.06    ______________________________________

The calculated results are for a compound having the approximate formulaC₈ H₁₃ NO and a molecular weight M of 139.198 g.

3. Infrared spectrum

The infrared spectrum of the compound obtained in accordance withExample 1 in the form of a film gives the following results:

    ______________________________________    Frequency of the    characteristic bands (cm.sup.-1)                       % Transmission    ______________________________________    2997               23.8    2932               28.9    2862               34.5    1738               45.8    1612               26.9    1591               20.5    1370               29.7    1322               19.7    1271               25.1    1129               20.6    1068               25.6     979               34.7     819               30.2    ______________________________________

4. NMR spectrum

The nuclear magnetic resonance spectrum of the proton of the compound intrichlorodeuteromethane (CDCl₃) at 20° C. shows the followingcharacteristic signals:

    ______________________________________                          Coupling    Signal   Multiplicity constant    (ppm)    of the signal                          (Hz)      Identification    ______________________________________    4.73     Doublet      2.6       H Olefinic    4.32     Doublet      2.6       H Olefinic    4.02     Triplet of a 2.0 and   2H-5             triplet      7.4    1.87     Quadruplet   7         2H Ethyl    2.73     Multiplet              2H-3    1.93     Multiplet              2H-4    1.42     Triplet      7         3H Ethyl    ______________________________________

Accordingly, the compound can be identified by these four tests as being2-(1-ethoxyethenyl)-1-pyrroline corresponding to the following formula:##STR2##

Example 3

a) Detection of the perception threshold by direct olfaction

Several aqueous solutions containing 2-(1-ethoxyethenyl)-1-pyrroline invarious concentrations are prepared.

50 ml of each solution accommodated in a 250 ml Erlenmeyer flaskprovided with a cover are presented to six tasters skilled in theanalysis of aromas.

The test is carried out as follows:

Three flasks are presented to each taster: one flask containing thearomatic solution and two flasks containing water. The taster has tosniff the head space and designate the flask containing the aromaticsolution. The test is repeated twice for concentrations of 1000, 100,10, 5 and 1 ppm.

The following results are obtained:

    ______________________________________    Concentration (ppm)                  1000    100     10     5    1    ______________________________________    Positive olfaction (%)                  100     100     100    50   17    ______________________________________

Accordingly, the perception threshold by direct olfaction is of theorder of 5 ppm.

b) Detection of the perception threshold by GC sniffing

The minimum quantity of 2-(1-ethoxyethenyl)-1-pyrroline detectable byolfaction is determined by GC sniffing (a combination of gaschromatography and olfactometry). To this end, solutions of the compoundin various concentrations are analyzed by gas phase chromatography.

After orientation tests, solutions of 2-(1-ethoxyethenyl)-1-pyrroline indichloromethane are prepared in concentrations of 100, 500 and 1000 ppm.

The analyses are carried out under the following conditions:

    ______________________________________    Chromatograph HP 5890 A (Hewlett Packard)    Capillary column                  DB wax (J and W Scientific),                  length 30 m, i.d. 0.25 mm    Detection     FID, 250° C. + sniffing port, 150° C.                  affluent splitting: 1/1    Injection     200° C., split (27.7 ml/min.)    Gas vector    helium, 17.5 psi    Furnace temperature:                  100° C. - 4° C./min. - 180° C.    Quantity injected:                  1 microlitre of a 1000 ppm solu-                  tion, i. e. 1 microgram of the com-                  pound.    Gas flows:    split vent = 27.7 ml/min.                  column effluent = 0.6 ml/min.                  (sniffing port)    Quantity of 2-(1-ethoxyethenyl)-1-pyrroline arriving at    the sniffing port = 21.7 ng    Estimation of the air volume entraining the 2-(1-    ethoxyethenyl-1-pyrroline    Duration of olfactory peak = 5 seconds    Humidified air flow rate (make up) = 0.83 ml/sec.    Air volume estimated at 4.2 ml air.    ______________________________________

The perception threshold of 2-(1-ethoxyethenyl)-1-pyrroline is 21.7 ngin 4.2 ml air, i.e., 5.20 ng/ml air.

Example 4

2-(1-Ethoxyethenyl)-1-pyrroline is hydrolyzed by addition of 5 ml 10.5 Nhydrochloric acid to 67.74 mg 2-(1-ethoxyethenyl)-1-pyrroline at 0° C.The mixture is then left standing for 2 hours at ambient temperature(25° C.).

The mixture is then cooled to approximately 5° C. and neutralized bydropwise addition with continuous stirring of 52.5 ml 1N sodiumhydroxide. An aqueous solution containing 97% 2-acetyl-1-pyrroline,i.e., 52.40 mg, and 3% 2-acetyl-2-pyrroline, i.e., 1.62 mg (compositiondetermined by gas phase chromatography and mass spectrometry) isobtained.

Example 5

2-(1-Ethoxyethenyl)-1-pyrroline is hydrolyzed by addition of 5 ml 1Nhydrochloric acid to 69.81 mg 2-(1-ethoxyethenyl)-1-pyrroline at 0° C.The mixture is then left standing for 7 days at ambient temperature (25°C.) so that hydrolysis is complete.

The mixture is then cooled to approximately -5° C. and the hydrolyzedmixture is diluted with 40 ml water and then neutralized by dropwiseaddition with continuous stirring of 5 ml 1N sodium hydroxide.

An aqueous solution containing 54 mg 2-acetyl-1-pyrroline (97%) and 1.67mg 2-acetyl-2-pyrroline (3%) is obtained.

Example 6

70 ml 1N HCl are added to 1.00132 g 2-(1-ethoxyethenyl)-1-pyrroline(i.e., 7.20 mmol) at 0° C. and the mixture is left standing for 7 daysat ambient temperature.

A first sample A of 17.5 ml of this reaction mixture is diluted in 175ml water and cooled to 0° C. 17.5 ml 1 N NaOH and an aqueous solutioncontaining 17.6 g maltodextrin, 2.4 g gum arabic and 430 ml water arethen added dropwise. The solution thus obtained is freeze-dried in astandard freeze dryer. A white powder containing 2-acetyl-1-pyrroline ina concentration of 1.0, based on the maltodextrin/gum arabic mixture,and in a concentration of 0.94%, based on the powder, is obtained.

Example 7

A sample B of 13.125 ml of the reaction mixture obtained in Example 6 isdiluted in 130 ml water and cooled to 0° C. 13.125 ml 1N NaOH and thenan aqueous solution containing 15 g β-cyclodextrin in 400 ml water arethen added dropwise. The solution thus obtained is freeze-dried as inExample 6. A white powder containing 2-acetyl-1-pyrroline in aconcentration of 1.0, based on the β-cyclodextrin, and in aconcentration of 0.94% based on the powder, is thus obtained.

Example 8

A sample C of 13.125 ml of the reaction mixture obtained in Example 6 isdiluted in 100 ml water and then cooled to 0° C. 15.0 g β-cyclodextrinin powder form and 13.125 ml 1N NaOH are then added. After stirring for30 minutes at 0° C., the solution is freeze-dried as in Example 6. Inthis case, freeze-drying is easier to carry out because the volume ofwater is much smaller by comparison with Examples 6 and 7.

A white powder containing 2-acetyl-1-pyrroline in a concentration of1.0%, based on the β-cyclodextrin, and 0.94%, based on the powder, isobtained.

Example 9

A sample D of 13.125 ml of the reaction mixture obtained in Example 6 isdiluted in 130 ml water and cooled to 0° C. 13.125 ml 1N NaOH and anaqueous solution containing 1.5 g β-cyclodextrin in 40 ml water are thenadded dropwise. The solution thus obtained is freeze-dried as in Example6. A white powder containing 2-acetyl-1-pyrroline in a concentration of10.0%, based on the β-cyclodextrin, is obtained.

Example 10

The stability of the 2-acetyl-1-pyrroline prepared in accordance withExamples 6 to 9 is studied over a period of 110 days at various storagetemperatures. To this end, samples of 100 mg freeze-dried powder aretaken after storage and dissolved in 1 ml water at 0° C. 1 ml ethylacetate containing 1 mg trimethyl-2,4,6-pyridine is added and themixture is stirred for 30 seconds. The mixture is then centrifuged for15 minutes at -5° C. and the organic phase is recovered and analyzed bygas phase chromatography.

The percentage of 2-acetyl-1-pyrroline being decomposed after 110 daysstorage is then determined. The following results are obtained:

    ______________________________________    Support and % decomposition of 2-acetyl-1-pyrroline    Storage  Maltodextrin                         β-Cyclodex-                                     β-Cyclodex-    temperature             1%          trin 1%     trin 10%    ______________________________________     20° C.             Complete de-                         99%         91% After             composition             13 days             after 50 d      4° C.             33%         10%         13% After                                     23 days    -20° C.             13%          0%         --    ______________________________________

It can be seen that 2-acetyl-1-pyrroline in a concentration of 1% onβ-cyclodextrin remains stable for at least 110 days when stored at a lowtemperature. This is also the case, although to a lesser extent, if the2-acetyl-1-pyrroline is encapsulated in a concentration of 1% onmaltodextrin/gum arabic. By contrast, the stability of the2-acetyl-1-pyrroline decreases when its concentration on the support (inthe present case β-cyclodextrin) increases. By comparison, 95% pure2-acetyl-1-pyrroline prepared in accordance with the prior art degradesrapidly in storage at -20° C. (Buttery et al., Journal of Agric. FoodChem. (1983), 31, 823-826).

Example 11

1 ppm 2-acetyl-1-pyrroline in a concentration of 1% on β-cyclodextrin isadded to a corn soup just before consumption. The soup thus prepared anda control soup containing no 2-acetyl-1-pyrroline are presented to agroup of six trained tasters. The 2-acetyl-1-pyrroline contributestowards a rounder, more cooked and more pleasant perception of the food.The "cooked cereal", "popcorn" and "very slightly grilled" notes arestrengthened and developed together with a very fine "buttery-fresh"note.

Example 12

1 ppm 2-acetyl-1-pyrroline in a concentration of 1% on β-cyclodextrin isadded to a chicken soup just before its consumption. The soup thusprepared and a control soup containing no 2-acetyl-1-pyrroline arepresented to a group of six trained tasters. The 2-acetyl-1-pyrrolinecontributes towards reducing the "chicken fat" note and strengthens the"chicken meat" and "slightly grilled" notes. The whole is more cookedand more complete and the slight "grilled meat" aftertaste is prolonged.

Example 13

1 ppm 2-acetyl-1-pyrroline in a concentration of 1% on β-cyclodextrin isadded to a beef soup just before consumption. The soup thus prepared anda control soup containing no 2-acetyl-1-pyrroline is presented to agroup of six trained tasters. The 2-acetyl-1-pyrroline contributestowards strengthening the "slightly grilled meat" note. The impressionin the mouth is more round and the beef aftertaste is prolonged.

Example 14

A composition of the "breadcrust" type is prepared by adding thefollowing compounds to 1 liter ethanol: 50 g 2-acetyl pyrazine, 10 g2-acetyl thiazole, 30 g diacetyl, 5 g 2-ethyl-3-methyl pyrazine. 0.1 gof this composition is added to 1 liter water previously salted with 3 gNaCl per liter. The aqueous mixture is divided into two batches. 0.5 ppm2-acetyl-1-pyrroline in a concentration of 1% on β-cyclodextrin is addedto the first batch. The second batch serves as control. A panel of tenpeople compares the two batches. The first batch appears better than thesecond with a strengthened "cereal", "breadcrust" note and a rounded"grilled" note. The whole remains longer in the mouth. When added to apizza dough, the present composition strengthens the "breadcrust" note,above all on olfaction.

Example 15

A composition of the "corn" type is prepared by adding the followingcompounds to 1 liter ethanol: 5 g 2-acetyl pyrazine, 5 g 2-acetylthiazole, 0.5 g diacetyl, 20 g dimethyl sulfide. 0.1 g of thiscomposition is added to 1 liter water salted beforehand with 3 g NaClper liter the aqueous mixture is divided into two batches. 0.5 ppm2-acetyl-1-pyrroline in a concentration of 1% on β-cyclodextrin is addedto the first batch. The second batch serves as control. A panel of 10people compares the two batches. The first batch has a more marked, morecomplete and more powerful "sweet corn" and "popcorn" note. Persistencein the mouth is more pronounced.

Example 16

A composition of the "potato" type is prepared by adding the followingcompounds to 1 liter ethanol: 5 g 2-acetyl thiazole, 5 g trimethylpyrazine, 0.5 g diacetyl, 2 g 2-ethyl-3-methoxypyrazine, 50 gmethylthio-3-propanal. 0.1 g of this composition is added to 1 literwater salted beforehand with 3 g NaCl per liter. The aqueous mixture isdivided into two batches. 0.5 ppm 2-acetyl-1-pyrroline in aconcentration of 1% on β-cyclodextrin is added to the first batch. Thesecond batch serves as control. A panel of 10 people compares the twobatches. The first batch appears better than the second and has a morecomplete and strengthened note of the "cooked potato flesh" type.

We claim:
 1. A powder-form composition comprising 2-acetyl-1-pyrrolineincorporated with a support selected from the group consisting ofcyclodextrin and maltodextrin.
 2. A composition according to claim 1wherein the support is cyclodextrin and wherein the 2-acetyl-1-pyrrolineis in an amount of up to 20% by weight of the composition.
 3. Acomposition according to claim 1 or 2 wherein the support isβ-cyclodextrin.
 4. A composition according to claim 1 wherein thesupport is maltodextrin and wherein the 2-acetyl-1-pyrroline is in anamount of up to 10% by weight of the composition.
 5. A compositionaccording to claim 1 or 4 wherein the support is maltodextrin and thecomposition further comprises gum arabic.
 6. A product of a process forpreparing a flavoring composition comprising:hydrolyzing a2-(1-alkoxyethenyl)-1-pyrroline compound with an acid to obtain areaction medium; adding an equimolar amount of a base to the reactionmedium to obtain a neutralized reaction medium containing2-acetyl-1-pyrroline; combining cyclodextrin with the neutralizedreaction medium so that a support solution containing up to 20%2-acetyl-1-pyrroline by weight based on the weight of the cyclodextrinis obtained; and freeze-drying the support solution to obtain theproduct.
 7. A product of a process for preparing a flavoring compositioncomprising:hydrolyzing a 2-(1-alkoxyethenyl)-1-pyrroline with an acid toobtain a reaction medium; adding an equimolar amount of a base to thereaction medium to obtain a neutralized reaction medium containing2-acetyl-1-pyrroline; combining maltodextrin with the neutralizedreaction medium so that a support solution containing up to 10%2-acetyl-1-pyrroline by weight based on the weight of the maltodextrinis obtained; and freeze-drying the support solution to obtain theproduct in powder-form.
 8. A product according to claim 6 wherein thecyclodextrin is β-cyclodextrin.
 9. A product according to claim 7further comprising combining gum arabic together with the maltodextrinand the neutralized reaction medium.
 10. A product according to claim 7further comprising combining cyclodextrin with the maltodextrin and theneutralized reaction medium.
 11. A product according to claim 10 whereinthe cyclodextrin is β-cyclodextrin.
 12. A product according to claim 6or 7 wherein the 2-(1-alkoxyethenyl)-1-pyrroline compound is2-(1-ethoxyethenyl)-1-pyrroline.
 13. A product according to claim 6 or 7wherein the acid is hydrochloric acid and the base is sodium hydroxide.14. A product according to claim 6 or 7 wherein the process is carriedout at a temperature of from -10° C. to 25° C.
 15. A powder-formcomposition comprising synthetic 2-acetyl-1-pyrroline incorporated witha support selected from the group consisting of cyclodextrin andmaltodextrin.
 16. A composition according to claim 15 wherein thesupport is cyclodextrin and wherein the 2-acetyl-1-pyrroline is in anamount of up to 20% by weight of the composition.
 17. A compositionaccording to claim 15 or 16 wherein the support is β-cyclodextrin.
 18. Acomposition according to claim 15 wherein the support is maltodextrinand wherein the 2-acetyl-1-pyrroline is in an amount of up to 10% byweight of the composition.
 19. A composition according to claim 15 or 18wherein the support is maltodextrin and the composition furthercomprises gum arabic.